Company email (November 2012):
[I contacted Kahlua just to double-check that the sugars used are vegan and not bone-char processed, and inquired about what they consider 'caramel color'. Martin replied very kindly (superb customer service) with this]
"Sorry for the late reply, I wanted to check with the chemist regarding your questions. Our chemist responded:
"The sugar is not filtered through bone char. The sugars used are considered vegan. We do not use white refined sugar. Caramel is also considered vegan as no components are derived from animal origin. If you have any further questions, please don't hesitate to ask."

From the FAQ (December 2011)
http://www.kahlua.com/ca/legal/contact/"Kahlua and Kahlua Flavors are suitable for Vegans. However, the Kahlúa Drinks-to-Go (DTGs) and the Kahlúa Ready-to-Drink (RTDs) contain milk proteins. Therefore, they're not okay for vegans but okay for vegetarians."

Update (2009)
"Kahlua Especial and Kahlua Mocha are also vegan. Company email: The Kahlua Especial is just like our regular Kahlua but the alcohol content higher. The Kahlua Mocha is a blend of 100% Arabica coffee, rum, natural vanilla and real dark chocolate."

Company email:
"The Kahlua Ready To Drink and Drinks To Go both have dairy.
The regular Kahlua, Kahlua Vanilla and Kahlua Hazelnut do not.